Question

In 1967 Otto Von Guericke, inventor of the air pump, evacuated
asphere made of two brass hemispheres. Two teams of eighthorses
each could pull the hmeisperes apart, only on some trialsand then
with greatest difficulty with the resulting sound likenedto a
cannon firing.

(a) Show that the force F required to pull the evacuated
hemisphereapart is
πR2x (P0-P), where R is the radius ofthe
hemispheres and P is the pressure inside the hemispheres ,which is
much less than P0.
(b) Determine the force, taking P= .100P0 and
R=.300m